According to the U.S. Surgeon General’s Report on Mental Health and Children, 11 percent of youth between the ages of 9 and 17 have a major mental illness. That’s close to 4 million kids. A similar number suffer from less serious mental health problems. And in both cases, the problems go mostly undiagnosed.

The American Psychiatric Foundation, a charitable and educational arm of the American Psychiatric Association, has launched a program for high schools to help teachers and counselors identify the warning signs of mental illness and point teenagers towards help.

“The earlier the better,” says Steven A. Rubloff, executive director of the American Psychiatric Foundation. “What we know about mental illness is that the bigger the gap between detection and treatment, the poorer the results. And right now, there’s a significant delay between the onset of mental illness and detection.” The school program "Typical or Troubled?" trains those adults who normally interact with teens at school to notice some red flags.

As a parent, you can help, too. Here are some of the things to look for:

Marked change in school performance, sleeping, and/or eating habits.

Inability to cope with problems and daily activities.

Many physical complaints.

Sexual acting out.

Depression shown by sustained, prolonged negative mood and attitude, often accompanied by poor appetite, difficulty sleeping, or thoughts of death.